Various forms of external, synthetic joints have been developed in the past for limiting or assisting in joint articulation during therapy or convalescence. Such joints typically attempt to mimic the articulation of the associated joint, usually in two dimensions. Thus, all commercially available external hip joints will enable articulation of the wearer's leg through flexion and extension, but not all enable abduction and adduction. But none, to the inventors' knowledge provide for unrestricted true circumduction, a natural and desirable capability provided for in "ball" type joints such as the human hip. And none provide the abduction, adduction, flexion and extension through a single point on an axis as does the natural hip joint.
It therefor becomes desirable, for expediency in prescribing treatment, in fitting orthoses, and ultimately for effective treatment of various conditions; to obtain an external orthotic appliance that will afford adjustable, controlled three dimensional motion or traction through a single point.
The present invention therefor has for an object, provision of a multi-axial external joint that will facilitate adjustable positioning of a selected limb in three dimensions about a single point.
Another object is to provide such a joint that will enable limited movement of a selected limb in any direction about the single point.
A still further object is to provide such a joint that enables articulation of a selected limb in a manner emulating the natural articulation of an associated joint for the selected limb.
The above and still further objects and advantages will become apparent from the following detailed description which exemplifies a preferred form of the present invention.